LAKE-EFFECT SNOWSTORMS (Recent and Historical)

The first half of December saw two remarkable lake-effect snowstorms in New York State (and a third more widespread and typical event December 12-15). The first occurred December 1-3 in the Buffalo area as a result of a persistent flow of cold air from the southwest over Lake Erie. A narrow 12-mile wide band of extremely intense snowfall set up just to the south and east of downtown Buffalo. The maximum total was 42” at Depew (7 miles east of Buffalo) over a 24-hour period ending at 8 a.m. on December 3. West Seneca (about 7 miles southeast of downtown Buffalo) totaled 30” with 7” of this falling in just one 30 minute period between 3:30 p.m.-4:00 p.m. on December 2nd according to local storm spotters. If true, this would be one of the, if not the, most intense point snowfall on record anywhere in the world. Unfortunately, for motorists, a 15-mile section of Interstate-90 passed through the area of intense accumulation resulting in the closure of this major highway for a 12-hour period. Hundreds of travelers were trapped in their vehicles for the duration of the highway closure and the New York State Highway Department became the focus of much criticism concerning their inability to open the road in a more timely fashion.

The second major lake-effect snow centered around the Syracuse, New York region between December 5-9. This time it was caused by a northwesterly wind flow off Lake Ontario. An official 44.3” five-day total (43.2” in four days) was measured at Syracuse’s Hancock International Airport. The weather service at the airport reported an amazing 97 consecutive hours of snowfall ending at 8 a.m. on December 8. Then the snow stopped for only one hour before resuming for another consecutive 23-hour stretch into the morning of December 9th. Storm spotters reported up to 58.2” total accumulation in other parts of the city. The village of Ferner, in Madison County and 20 miles southeast of Syracuse, reported a 50.6” accumulation. Lacona, in perennially snowy Oswego County, reported 51.5”. The Canadian snow belt in Ontario downwind from Lake Huron reported even more fantastic snowfalls including 60” (153cm) at Lucan twenty miles north of the city of London (which recorded a 47.2”/120cm accumulation smashing its previous single-day snowfall record of 22.4”/57cm set on December 7, 1977).

London, Ontario buried under more than three feet of snow on December 8. (photo by Tim Dann)

A third more general lake-effect snowfall affected all the Great Lake snow belts following the record synoptic snowfall over the Upper Midwest (most notable records being the 22.0” in Eau Claire, Wisconsin on December 11th, their all-time 24-hour and single-biggest-snowstorm on record and 17.4” in Minneapolis, a December record). The arctic air blast following the blizzard resulted in significant but not extraordinary lake-effect snows between December 12-15 in northern Indiana (up to 17”), northeastern Ohio and western Pennsylvania (up to 38” at Corry, Pennsylvania), and in the usual areas of upstate New York (up to 22”).

Historic Lake-effect Snowfalls

So how do these recent events compare to other historical lake-effect snowstorms? Exceptional but, for the most part, not record-breaking believe it or not. The Great Lakes of North America, being the largest fresh water bodies in the world, are unique in producing extraordinary snowfalls of this nature. The fact that they remain mostly ice-free all winter (except for Lake Superior) means that these snowfalls may occur during any winter month, although it is usually in the late fall (November and December) when the greatest accumulations occur since the lake waters are still relatively warm and able to provide more vapor to the atmosphere.

(Sorry about this lousy graphic, but all good detailed maps of the snow belts of the U.S.A. and Canada only show either just the U.S.A. snow belts (with accumulation statistics) or just the Canadian snow belts. This is because the Canadians use metric units and the U.S. English units, so a comprehensive map detailing the amounts of snowfall over the entire region are non-existent so far as I am aware).

When conditions are just right, the snow rates during some events are the greatest ever measured on record from anywhere in the world. The 7” in 30 minutes at West Seneca, NY (mentioned above) is an example. (It is conceivable that snow rates just as great may occur in the high altitudes of Washington’s Olympic Mountains or other high elevations of the coastal mountains of British Columbia and Alaska, but there are no actual measurements of such).Other world-record point snowfalls from the Great Lakes region include:

12.0” in 1 hour at Copenhagen, New York on Dec. 2, 196617.5” in 2 hours at Oswego, New York on Jan. 26, 197222.0” in 3 hours at Valparaiso, Indiana on Dec. 18, 1981 51.0” in 16 hours at Benetts Bridge, New York on Jan. 17-18, 1959

…and the granddaddy of all snowfalls: the 77.0” in 24 hours reported in Montague Township on the Tug Hill Plateau of New York on Jan. 11-12, 1997. This would be the world 24-hour snowfall record (surpassing the 75.8” at Silver Lake, Colorado on April 14-15, 1921) if the observer had made his measurements slightly more exacting. Unfortunately, he made one too many measurements during the period of snowfall and the record was consequently rejected as official by the National Weather Service’s Snowfall Evaluation Committee. The storm total was 95” over a three day period. At times the snow fell so heavily that snowplow operators could not see further than ten feet in front of their vehicles.

A photo of the remarkable accumulation in Montague Township, New York on the morning of January 12, 1997. (photo by Cheryl Boughton)

Buffalo’s single greatest lake-effect (for that matter any) snowstorm occurred December 24-28, 2001 when 81.5” accumulated at the official city weather service site at the airport. The same event also affected the Lake Michigan snow belt around Petoskey, Michigan where a state-record for a single snowstorm dropped 85.0” between December 23-29.

A remarkable aerial view taken from a local news helicopter of an intense snow squall enveloping Buffalo during February 2007. Four inches of snow fell in a very short period of time as the squall passed over the city. (from snopes.com)

In October 2006 a freak early-season lake effect snowstorm dropped up to two feet of heavy wet snow at the Buffalo airport resulting in the incredible sight of commercial aircraft tipped back onto their tails as a result of the weight of the snow!

(photo by John Wichrowski)

New York State’s record for a single snowstorm buried Oswego under 102” of snow between January 27-31, 1966 (the same lake-effect event that resulted in Syracuse’s greatest 4-day total of 44.6”). Oswego has a long history of extraordinary snowfalls including one in February 1856 that buried the town with four to ten feet of snow with drifts as deep as thirty feet according to local reports (see David Ludlum’s Early American Winters: 1821-1870 page 226-227 for more about this amazing event).

Other Great Lakes locations that regularly record phenomenal lake-effect snows include the Upper Peninsula of Michigan, northern Indiana’s Lake Michigan shoreline counties, and the hills of northeastern Ohio and Pennsylvania just south and east of Lake Erie. The state greatest-single-snowstorm records for Indiana, Ohio, and Pennsylvania (as well as Michigan and New York) are all the result of lake-effect snowfalls:

The Upper Peninsula of Michigan hosts the snowiest places in the United States east of the Rocky Mountains (aside from the summit of Mt. Washington) thanks to persistent snow squalls blowing off Lake Superior and unloading their precipitation over the hills of the Keweenaw Peninsula and the Huron Mountains west of Marquette. A dot on the map in this area named Herman takes top honors with an average of 236” of snow each winter season (Mt. Washington averages 310”).

Other lakes in the United States that regularly produce accumulating lake-effect snow squalls include The Great Salt Lake of Utah and Lake Champlain bordering Vermont and New York. In Canada Lake Winnipeg and the other large Canadian lakes produce modest lake-effect snowfalls early in the season before they freeze over.

For a good overview on the causes of lake-effect snowfalls and other places around the world that experience the phenomena see: http://en.wikipedia.org/wiki/Lake-effect_snow

November 2010 Weather Extremes Summary

I plan to begin a monthly blog concerning various extreme weather events and records for each month from around the world. This entry, for November 2010, will be the first. This will be by no means a complete list of all the various extreme weather events from around the world, but simply a summary and mention of some of those of note.

This monthly blog will be fluid, meaning that I plan to update it as time goes on (during the month following the initial posting), and weather records trickle in during the weeks following my initial post. These 'post original comments' will be highlighted in bold type. So I would appreciate any information relevant to the month concerned that should be worthy of mention that I may have overlooked. Check back to the blog from time-to-time to view updates.

UNITED STATES

For the United States, November is usually the month of transition from Fall to Winter. Thus, the U.S. normally experiences a wide variety of weather extremes, especially those regarding temperatures. This past November was no exception.

The most dramatic temperature change was that affecting the western half of the nation. An exceptionally cold second half followed a very warm first half of the month. San Diego, California measured an amazing 100° on November 4th, not only the warmest temperature ever recorded in November (previous record was 97° on Nov. 1, 1966), but the latest date of a 100° reading on record, beating the previous such by two weeks (104° on Oct. 22, 1965). By the last day of November, San Diego temperatures had fallen to 42°, just 2° above the record low for the date. The San Francisco Bay Area saw record high temperatures in the lower 80°s on Nov. 15 fall to record low temperatures in the mid-30s by Nov. 24. Seattle tied its all-time warmest November temperature of 74° on Nov. 3, before falling to a record low of 14° on November 24 (along with several inches of snow).

Measurable snowfall was reported at sea level as far south as Brookings on the southern Oregon Pacific coastline on November 23. Billings, Montana fell from a record 71° on November 2 to a record -14° by November 24. The city also recorded 21.3" of snow for the month, just short of the November record of 25.2" in 1978. Exceptionally heavy snowfall was measured at all mountain locations in the West; the 139" at Rendezvous Bowl in Jackson Hole, Wyoming was the greatest amount so early in the season ever recorded. Ten feet of snow fell in the Sierra Nevada ski resorts during the last week of the month, and similar amounts piled up in the Colorado and Utah ski locations.

The opposite held sway for locations in the East where little or no snowfall was recorded at most New England and Appalachian locations, although snowless Novembers have occurred several times in the past as well.

A 'blue norther' swept Texas on November 25-26 sending temperatures plunging; San Antonio fell from 83° on the 25th to 28° on the 26th and Junction from 81° to 18°, Laredo fell from 91° to 37°.

There were no notable record extreme precipitation events anywhere in the lower 48 states.

Several tornado outbreaks worthy of note occurred: Wisconsin and northern Illinois on November 22 injuring several people and damaging homes in Caledonia, Illinois and Union Grove, Wisconsin. This was one of the latest tornado outbreaks on record for this area. A tornado swarm, including a couple of F-2’s, hammered the Southeast on November 30.

EUROPE

November was one of the coldest on record for some portions of Western Europe. In fact, for the central region of Norway, it was the coldest November on record. The monthly absolute minimum temperature for the country was -35°C (-31°F) at Karasjok on November 26, one of the coldest November readings on record during a November. Ireland actually did record its coldest November temperature on record when a reading of -13.7° C (7.3°F) was registered at Casemont Aerodrome in Baldonnel on November 28 (Ireland’s national all-time coldest temperature was -19.1°C/-2.4°F at Markree Castle back in January 1881). Dublin also recorded its coldest November temperature on record that same day with an -8.8°C (16°F). The previous record was -6.7°C (20°F). In the United Kingdom the coldest reading was -21.2°C (-6.2°F) at the Scottish highland’s village of Altnaharra. This was just 2°C higher than the coldest November reading on record for anywhere in the United Kingdom. Heavy snowfall accompanied the cold during the last week of the month with a very rare 5" accumulation in Dublin (greatest November snowstorm in history.) Record November snowfalls closed airports throughout the United Kingdom. Edinburgh, Scotland received 16" of snow with some parts of England and Scotland reporting up to 4 feet of snow. Even parts of London received almost 10" of snow during the last days of the month.

Figure 1. Edinburgh, Scotland buried under 16" of snow, November 2010. Photo courtesy of The Scotsman newspaper in Edinburgh.

In Geneva, Switzerland 12" of now fell on Nov. 30-Dec.1, the fourth heaviest snowfall for that city since 1895. The Italian Alpine ski resort of Sestiere recorded 60cm (2 feet) of snow in one 24-hour period the last day of November.

Ironically, Eastern Europe including Moscow, endured an unusually warm month until cold air filtered in during the final week. Moscow recorded a temperature of 14.5°C (58.1°F) on November 11th, not only the warmest temperature ever measured so late in the season, but also the warmest November temperature on record (at VVC, Moscow’s official weather site location). Novosibirsk, in western Siberia reached 3.7°C (39°F) on November 15th, its warmest November temperature on record.

ASIA

By November 30th, however, temperature readings had fallen below zero Fahrenheit. In Siberia, the "coldest inhabited place on earth", Omyakon, bottomed out at -53.8°C (-64.8°F) on November 28th for the coldest reading measured on Earth (inhabited location) for the entire month of November 2010. Istanbul, Turkey recorded 78°F on November 15, also a record so-late-in-the-season temperature, but 2°F short of its all-time November record.

Southern India and Sri Lanka recorded exceptional rains as a result of Cyclone Jal. Colombo, the capital of Sri Lanka, recorded 445mm (17.5”) of rain in 24 hours on November 7th, its heaviest single-day rainfall since June 1992. The same storm system also brought record flooding rains to southern Thailand, where Hat Yai on the Kra Isthmus was flooded by 10 feet of water in its downtown district. Nearby Surat Thani measured an amazing 47.69" of precipitation during the month of November. The popular tourist resort of Ko Samui recorded 11.26" of rain on the single day of November 9th.

ANTARCTICA

The coldest reading for the month (and hence the world) was -71°F at Vostok on November 5th. Although not a November record, it is interesting to note that on December 1st the Dome Argus site recorded a temperature of -52°C (-61.6°F), which is the coldest temperature ever measured in the Southern Hemisphere during any December on record (nearing mid-summer, of course, for Antarctica).

SOUTH AMERICA

Deadly floods struck both Columbia (Nov. 8-22) and Venezuela (Nov. 25-30). Up to 16" of rain inundated areas around Bogota, Columbia and the death toll reached 136. In Venezuela, floods around Caracas killed 25.

AUSTRALIA

Australia has just completed its wettest Spring (September-November)on record with a nation-wide average of 163.0mm (6.42”) clearly besting the previous record of 140.1mm (5.52”) set in 1975. The greatest 24-hour total was 254.4mm (10.02”) at Noosaville, Queensland on October 9th. Lake Eyre has reached its greatest water accumaulation since 1990 as a result of this wet spring. Maximum temperatures averaged -1.23°C below average nation-wide for the Spring season, 4th coldest on record, but milder minimum temperatures caused the overall temperature ranking for Spring to be just about close to normal.

Thanks to Blair Trewin of the Australian Met. Dept. for the above information.

AFRICAOn November 26 a single lightning bolt apparently killed seven and injured 40 people at a nursery school party in Kwa Zulu, Natal Province in eastern South Africa. This would rank as one of the top ten deadliest such instances on record anywhere in the world.